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Old 19-10-2014, 09:57 AM
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Shiraz (Ray)
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Join Date: Apr 2010
Location: ardrossan south australia
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Quote:
Originally Posted by bert View Post
I think you guys maybe looking at guiding from the wrong perspective. Good guiding is good guiding at any focal length. Bad guiding can sometimes be hidden by imaging at a shorter focal length, so why not just go for good guiding?
I'm with Brett on this one - angular guiding errors are independent of imager focal length, so they just need to be good enough to hide below the seeing.

for example, 3.75 micron guide pixels (ASI120/QHY5L2) with a 180mm fl guidescope yield 4 arcsec pixels. With 10x sub pixel resolution in the guide software you can resolve 0.4 arcsec errors, which with 2 arc sec seeing and a good mount, should keep stars within about 10% of the seeing limited FWHM with any imaging system.
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